A widespread vehicle area network (VAN) which is internationally standardized according to ISO 11898 is familiar to a person skilled in the art as a controller area network (CAN). Wireless interfaces for such a vehicle area network are also known. However, an unauthorized third party can also access the vehicle area network via such an interface and can thus interfere with or paralyze the vehicle area network. It is therefore sometimes proposed to prevent write access (transmit, Tx) to the vehicle area network via the interface. However, no diagnoses or network management applications can be executed in this case via the interface.
DE 10 2011 051 758 A1, which is incorporated by reference herein, discloses a CAN bus adapter for connection to the CAN bus of a motor vehicle. The CAN bus adapter has at least one first interface for connection to the CAN bus of a motor vehicle and at least one second interface for wireless or wired connection to a computer or a device of that kind. The CAN bus adapter is distinguished by the fact that at least one buffer is provided and is designed to store the CAN bus data received from the first interface according to the first-in-first-out principle if necessary.
US 2010/0306457 A1, which is incorporated by reference herein, relates to a microcontroller having a random access memory and a CAN controller which has a control unit which receives an assembled CAN message, the control unit being set up to generate a buffer descriptor table entry using the assembled CAN message and to store this buffer descriptor table entry in the random access memory. The buffer descriptor table entry comprises at least one message identifier and useful data from the CAN message and information relating to a subsequent buffer descriptor table entry.
Finally, DE 41 26 850 A1, which is incorporated by reference herein, proposes a circuit arrangement for adapting a data bus controller module to a symmetrical bus line, in particular according to the CAN bus system, in order to add a reactance, which has been inserted into the transmission signal path from the controller module to the bus line and has a low shunt capacitance and a controllably variable inductance value, and a control circuit for temporally changing the inductance acting on the transmission signal current on the basis of signal edges of the transmission signal.
US 2013/0227648 A1, which is incorporated by reference herein, and US 2010/0174439 A1, which is also incorporated by reference herein, discuss similar apparatuses.